The present invention relates to a method of manufacture of a semiconductor device; and, more particularly, the invention relates to a technique for making an electrical connection from an inspecting device to a semiconductor device, that is formed in a semiconductor substrate, so as to carry out an inspection of the semiconductor device during the manufacture thereof.
A method of manufacture of a semiconductor device, such as an IC, an LSI, etc., is generally divided into a so-called pre-process, which includes steps carried out up to the formation of an integrated circuit on the surface of a silicon wafer, and a so-called after-process, which includes steps during which this silicon wafer is cut and separated into individual chips and is sealed by resin, ceramic, etc. In these semiconductor devices, the electrical characteristics of each circuit are inspected, and non-defective and defective products (chips) are judged in a chip unit at a predetermined stage during the pre-process.
With respect to “a probe structure body” that is used for the purpose of conducting an inspection with respect to a finely inspected object, such as an IC, electronic parts, etc., a bump contact projected in a hemispherical shape (dome shape) is formed to come into contact with the inspected object, and a concavo-convex structure is formed on the bump surface to improve the contact reliability. A known example is disclosed in laid-open in JP-A-9-133711 and JP-A-2001-250851. The former publication discloses a probe structure in which a bump contact arranged on one face of an insulating substrate and an electrically conductive circuit arranged on the other face are conductively connected. A very small projection is formed on the bump contact surface, and the probe structure is formed by a three-layer structure, including a deep layer made of nickel, a middle layer made of gold, and a surface layer made of rhodium. The latter publication also discloses a probe structure similar to that of the former publication, in which irregularities are formed by collecting very small grains on the bump surface. In both the former and the latter techniques, dull plating is applied as an irregular forming means.
In the structure of the bump surface described in the above-referenced publications, the inspecting contact portion of the bump surface has a large curvature, and so it is difficult to judge which portion of the bump comes in contact with the contact portion. It is also a problem that non of these structures is easily arranged at a high density, with the result that and it is difficult to cope with a product having a narrow pitch.
Further, when there are many object electrodes, it is difficult to control the height dispersion in the individual bump, since it is limited to a bump probe that is in contact with a very small area. Further, there is no specific description with respect to an appropriate contact pressurizing contact structure under such a situation.